DR ANDY BAKER, of Newcastle University, is hoping to answer the most frequently asked question at Stumps Cross Caverns, a set of caves under the Yorkshire Dales: how fast do stalagmites grow?

An award from the Royal Society and the British Association has enabled Dr Baker to install instruments deep underground that record rainfall, calcium levels and temperature - the key components in determining the rate of stalagmite growth.

Six stalagmites are being monitored with an interactive computer display in the visitor centre above ground.

Dr Baker hopes the the measurements will show the science behind the question and reveal the relationship between temperature, volume of carbon dioxide in the soil, levels of calcium in water and eventual growth.

However, visitors expecting to see a rapid sprout of brand new stalagmite are likely to be in for a disappointment. The average growth at Stumps Cross is one tenth of a millimetre a year.